Just a few things since you've got some time:
1. The Z is a great little sports car with grand touring tendencies; it's very drivable. But keep in mind this is still essentially a car from 2009. When it came out, it outgunned the Mustangs/Camaros and gave Boxsters a run on the twisties. Since then, pretty much all of these cars have had major revisions and moved onward. The Z is still great, but keep that in mind.
2. Go out and test drive some more similar cars if you can, so you're not just being sucked into the popular dealer tactic of getting your butt in the car so you fall in love with it because said butt is not used to such a vehicle (let alone a brand new one where everything works).
Maybe see if you can check out:
Camaro v6 and v8
Mustang v6 and v8
FRS/BRZ (you'll find it underpowered, but maybe just as fun?)
Porsche Boxster (overpriced, but the butt feel might be nice, if they let you test it)
BMW M235i if they're out, otherwise 335i(x). (High price, but can seem similar)
WRX and/or WRX STI
Hyundai Genesis Coupe
Make a list of what you like about the Z and/or what you like about a car you drive, test drive alternatives that offer that, and there you go.
You'll probably come back to the Z, so...good luck!
